Sökning: "giving-up density"
Hittade 3 avhandlingar innehållade orden giving-up density.
1. Through the eyes of a woodpecker: Understanding habitat selection, territory quality and reproductive decisions from individual behaviour
Sammanfattning : In this thesis I present some connections between foraging behaviour and reproductive success, time budget, tree species use, and habitat selection. The thesis is based upon both theoretical and empirical work. All empirical studies concern a south Swedish population of lesser spotted woodpeckers Dendrocopos minor, studied between 1990 and 1996. LÄS MER
2. Foraging behaviour in benthivorous fish
Sammanfattning : The foraging ability of an organism is essential since it affects various traits, e.g. growth, reproduction effort, social status and, ultimately, fitness. LÄS MER
3. Costs of foraging in a dry tropical environment
Sammanfattning : This study evaluates the costs associated with foraging for birds in a savannah woodland area in central Nigeria. Specifically, it looks at the following questions: 1) how does seasonal variability in food and water availability affect the value of resources to birds in dry environments? 2) Does proximity to water affect foraging decisions? What implication will this have in the management of savannah birds? 3) Are tropical birds mostly affected by metabolic or predation costs? 4) What factors affect diet selection in birds and how? 5) How are birds adapted to hot dry environments? I carried out experiments in the field and in an aviary and provided artificial food patches, consisting of feeding trays with seeds mixed in sand or pebbles (in the aviary study). LÄS MER